Flexible conduit and method of making



- Sept. 15, 1936. COWLES FLEXIBLE CONDUIT AND METHOD OF MAKING OriginalFiled July 13, 1935 ll/i III! i Patented Sept. 15, 1936 UNITED STATESPATENT OFFICE Irving Cowles, Detroit, Mich.

Original application July 13, 1933, Serial No. 680,200, now Patent No.2,008,175, dated July 16, 1935. Divided and this application June 28,

1935, Serial No. 28,839

3 Claims.

This invention relates to improvements in flexible conduits adapted tobe used for very high pressure purposes.

The main object of the invention is to produce a flexible conduit whichis rendered leak-proof at the point or points at which leakage is mostapt to occur under high fluid pressure within the conduit.

Other important and essential objects of the invention are pointed outin the following specification.

The method of the present invention is illustrated in and by theaccompanying drawing, wherein:

Fig. l is a central, longitudinal section of a die or tool employed inassembling a piece of flexible conduit with one member of a hosecoupling and discloses the first step in the method of the presentinvention and in part, the unfinished structure.

Figs. 2 and 3 are views similar to Fig. 1 illustrating the second andthird steps of the method of the invention.

Figs. 4 and 5 illustrate the further steps of effecting completion ofthe assembly of the structare including another member of the couplingemployed.

Fig. 5 shows the completed structure produced by the method aforesaid.

Fig. 6 is a central, longitudinal, perspective section of the bodyportion of the hose coupling employed.

Fig. 7 is a perspective, sectional view of a sleeve constituting a partof the coupling structure.

This application is a division of my original application for patentSerial No. 680,200, filed the 13th day of July, 1933, which eventuatedin the issuance of Patent No. 2,008,175 dated the 16th day July, 1935.

By reference to the drawing it will be noted (Fig. 5) that the flexibleportion of the conduit structure consists of a well-known type of metallined rubber hose wherein the inner wall I consists of a pair ofchanneled strips disposed in opposed overlapped relation to form acontinuous helical wall structure which is encased in the rubber tube 2.The latter may include a wire reinforcement 3 embedded therein, as

shown in Fig. 5, or may be devoid of such reiniorcement. Generallyspeaking, the rubber casing 2 is wrapped with a textile covering, butomitted from Fig. 5.

The flexibility of the wall I is such that contraction thereof willoccur under the influence of radial pressure on the external surface 01the casing 2 such as is relied upon generally to provide a fluid tightjoint between the flexible conduit and the metal coupling at the ends ofthe latter, thus limiting the degree of such ex- 5 ternal pressure to apoint less than that which will cause the wall I to contract. According-1 ly, the said contracting pressure of the coupling sleeve isinsufflcient to prevent leakage under the influence of a high degree offluid pressure with- 10 in the conduit structure. This is due to thefact that the fluid under very high pressure will penetrate through orpast the wall I and past the end of the rubber casing 2 where it abutsthe opposed wall of the metal coupling 15 and thus finds its way to theinner face of the tubular wall of the coupling which is compressedagainst the outer surface of the rubber wall 2 and, where this occursleakage will result.

In'the case of reinforced hose, such as is illus- 20 trated in Fig. 5,the fluid under pressure passing between the end of the rubber wall 2and the opposed wall of the coupling, will penetrate said rubber wallaround the wires of the reinforcing structure 3 and will soon destroythe 25 portion of the wall 2 outwardly of the reinforcement 3 and withinand beyond the coupling structure.

Obviously, if the wall 2 is wrapped with fabric and the latter extendsto the end of the hose 30 within the coupling, the penetration of fluidbetween the end of the hose and the opposed wall of the coupling willfollow the fabric wrapping very easily and cause leakage.

The main object of the invention is, therefore, to provide a method ofassembling a flexible conduit in such a manner as to prevent leakage offluid past the annular shoulder 5 of the coupling (which is opposed tothe end of the rub ber wall 2 of the flexible conduit) and the throat 406 of the coupling into which the lining I projects (see Fig. 6).

This is accomplished by crowding the wall 2 against the shoulder 5 withsufficient permanently 45 maintained force to prevent leakage asaforesaid under the influence of hose-bursting pressure, as shown inFig. 5.

I am aware that the prior art discloses conduit structures wherein theend of the rubber wall of 50 the hose abuts a shoulder similar to theshoulder 5 of the couplings illustrated in the accompanying drawing, butI do not know of any prior art disclosure of structure and method ofassembly of hose and coupling capable of producing the re- 55 sult whichI attain by means of the present inven- A mandrel 25 is mounted in thedie 24 and is tion. received telescopically in the bore of the. hose forThe coupling, per se, comprises the body portion 1 provided with acentral bore 8 of a diameter substantially equal to that of the wall Iof the conduit and which is concentric with the throat 6 andcommunicates therewith; the threaded nipple 9 shown as .a maleconnecting member; the annular grove I0 bordering the annular shoulder5; the outer annular flange II having an inner .cylindrical face flushwith the outer wall of the groove I0 and which is tapered externally;and

the sleeve I2.

The said sleeve I2 is initially cylindrical internally and. is providedat one end with a flared mouth I3 and, between its ends, with annulargrooves I4 which are spaced from the other end of the sleeve. Externallysaid sleeve I2 is also initially cylindrical and of slightly largerdiameter than the inner diameter of the flange. II of the couplingexcept along the end portion I5 of said sleeve which is adapted to bereceived telescopically within said flange II and the annular grooveIII.

The assembly of the flexible conduit structure is effected as follows:

A die (Fig. 1) is provided which consists of a heavy cylindrical blockll of steel which is equipped with a central opening which receives theshank I8 of a head I9 of larger diameter than said shank I8 and whichcorresponds substantially in shape and in size with that portion of thecoupling lying within the cylindrical plane of the inner surface of theflange II except as described hereinafter. This head is disposedtelescopically within the central opening of a head 20 which is equippedwith an outer annular flange 2| within which one end portion of theblock I'I 'isreceived telescopically.

The shank I8 terminates in a smaller diameter shank 22 which is receivedtelescopically within a portion of the central opening of the block I Iand is secured therein by means of the crosspin 23.

It will be noted that the heads I9 and 20 cooperate with each other todeflne an annular groove corresponding to the groove Ill of thecoupling, but of appreciably less depth than the latter. This groovereceives a part of the end portion I5 of the sleeve II and said sleevereceives an end portion of the hose.

It will be observed by reference to Fig. 1 that the rubber wall 2 of thehose has been cut away so that the inner wall I thereof projects fromthe body of the hose so that when the hose has been inserted into thesleeve II until the rubber wall engages the opposed annular shoulder ofthe head I9 which corresponds substantially with the annular shoulder 5of the coupling, the projecting end of the wall I is disposed within thecentral aperture of the head I9 which corresponds to the throat 6 of thecoupling.

The hose fits the sleeve II so snugly that said sleeve will remainfirmly in place on the hose as said sleeve and hose are withdrawn fromthe heads I9 and 20 and are inserted into the die 24 shown in Fig. 2.Said die 24 corresponds in shape and size with the portions of the headsI9 and 20 which cooperate to position the sleeve upon the hose asdescribed above, the outer annular flange 5 of the die 24 being oflength and shape to receive all of the end portion I5 and part of thebody portion of the sleeve I I and is equipped with an internal shoulder26 against which the shoulder I6 of the sleeve II abuts.

groove II) of the coupling.

a length in excess of the sleeve II.

The die 24 is disposed above a suitable sleeve contracting die 28 and isforced downwardly by means of the plunger 29 of a punch press to causethe outer end portion of the sleeve I2 to be contracted upon the hose asillustrated in Fig. 3.

This progressive contraction of the sleeve II effects a displacement ofthe rubber of the wall 2 and crowds the displaced material inwardly andagainst the annular shoulder of the die 24 which is opposed to 'the endof said rubber wall.

It will be apparent that the annular shoulders of the dies I9 and 24which are opposed to the rubber wall 2 of the hose, are shapeddifferently than the annular shoulder 5 of the coupling and also thatthe depth of the annular groove III of the latter is of greater depththan the similar grooves of the aforesaid dies.

The operation illustrated in Figs. 2-and 3, as above described, servesto cause the sleeve I2 to. be mounted so firmly on the hose as toprevent any relative movement between said sleeve and hose in performingthe final step of the method of this invention.

The latter consists in leaving the sleeve I2 and.

the hose secured therein in the die 28, withdraw-'- ing the die 24, thenmounting the coupling upon the sleeve and hose assembly as shown in Fig.4

wherein said coupling is shown as forced down upon the sleeve I2 toflnal position by means of the plunger 29 during the initial downwardstroke thereof, the continuation of said stroke causing the flange I Iof the coupling to be contracted upon the tapered portion of the thinnerend portion II of the sleeve I2 to complete the assembly.

Obviously, the die 28 must consist of separable members which are heldsuitably against separation during the aforesaid assembly operationswhich are effected at both ends of a hose length to complete the conduitfor commercial use.

In the final operation, as illustrated in Figs. 4"

I claim as my invention:

1. The method of making fluid-tight, fleidble conduits which consists inproviding a coupling member for each end of the conduit presenting an.annular shoulder opposed to an extremity .of-- the conduit and equippedwith an annular contractible shell of larger inner diameter than thehose andadapted to receive a portion of the lat-. ter, then mounting andsecuring upon the hose end a contractible sleeve in predetermined spacedrelation to the extremity of the hose, then inserting an end portion ofthe tubular memberinto the annular flange of the coupling member tobring the extremity of the hose into contact with said annular shoulder,then moving said tubular member farther into said flange for com-.

pressing said hose extremity against the shoulder with a forcesuflicient to change the position of said extremity relative to thetubular member,. and then, while maintaining said tubular member in saidlast-named position. contracting said flange into permanent engagementwith said tu bular member.

members for eachend portion: of a hose, each consisting of two members,one, thereof, comprising a body portion equipped. with a substantiallycylindrical cont'raotible shell and withan annular cylindrical groovehavingits outer-wall flush with the inner surface of said shell ands'ur'-' rounding an annular shoulder: adapted'to engage an extremity ofthe hose-and the other member of said coupling consisting of acontractible sleeve of an outer diametersubstantiallyequal-to the innerdiameter ofthe said shell,-said sleeve being of a length greater thanthe distance separating the outer end of the shell from the-bottom ofsaid groove, said method consisting in first contracting one end portionof said'sleeve upon an end portion of the hose, while said'sleevprojects beyond an extremity of the hose a'distance less than that ofthe bottom of said groove in the said shoulder, then inserting thelast-named end portion of thesleeve into the shell until the extremityof the hose abuts against said shoulder, then forcing said sleeve intosaid shell and groove to a position wherein the'hose extremity isforcedback into saidsleeve and while holding said sleeve insaidlast-named'position, contracting said shell into permanent engagementwith said sleeve.

3. The method of making-fluid-ti'ght, flexible conduits whichconsists-in providing a flexible hose lengthya two piece coupling foreach end portion of the hose, each coupling 'includingabodymember'equipped with-cylindrical contract-I ible shell bordering anannular shoulder opposed to-an extremityiofthe hose, and a substantiallycylindrical contractible-sleeve of greater" length,

than said shell and'adapted'to be received telescopically within thelatter along one endpor tion, said method consisting-"in firstcontracting" one end portion of a sleeve upon an end portionof the hosewhile maintaining said sleeve with one end thereof spaced the adjacentextremity latter into permanent engagement with said" sleeve to retainthe same insaid last-named po-' sition.

IRVING COWLES.

